Lighting fixture



Patented Jan. 4, 1927.

HENRY Dfomnnan., or isn.11)enieoiew:.cernvncricinr.'`

LIGHTING FIXTURE.

Application filed December 17. '1924, lSerial No. 756,384.

My invent-ion relates to light distributing construction.

One of the objects of my invention is to provide a light distributingconstruction which will give an advantageous light distribution.

A further object of my invention is to provide a light distributingconstruction, comprising a translucent diffusing bowl and an opaquereflecting bowl in which diffused light will be distributed above theplane of the lower ed e of the reflecting bowl.

A further obJect of my invention is to provide an improved constructionin which free passage is provided for the downwardly directed raysbetween the diffusing bowl and the reflecting bowl.

Further objects will appear from the description and claim.

In the drawings, in which my invention is illustrated:

Figure 1 is a sectional perspective view showing a diffusing bowl withthe reflecting bowl surrounding it;

Fig. 2 is an axial sectional view through the two bowls; and

Fig. 3 is a table in which the lines corresponding to the various typesof rays are designated.

The construction shown comprises a diffusing bowl 10 which may besimilar to that shown in my prior pending application, Serial Number657,854, and a metal reflecting bowl 11 surrounding the diffusing bowland supported thereby. The only direct rays A are those which passthrough the opening in the lower part of the diffusing bowl.

The construction is such that neither direct rays A nor directreflection rays B escape from the diffusing bowl at a planev above theplane of the direct rays. By referring to Fig. 1 it will be seen thatsome of the second reflection rays C do escape *1 Vabove'the plane oicone of the direct rays. The diffused rays D which pass through theYdiffusing bowl are diffused and distributed in every direction and willtherefore be reflected in various directions from the inner reflectingsurface of the metal reflecting bowl.

It will Vbe noted that the lower edge 12 of the diffusing bowl extendssubstantially below the lower edge 13 of the outer reflecting bowl sothat diffused rays D passing through this lower extending portion willbe diffused and some ofthese diffused rays D will pass` above the planeof the lower edge of the outer reflecting bowl, thus giving a diffusedlight in a higher plane than could be obtained with the use of the metalreflecting planealone.

It will be noted that the skirt portions 14 and 15, respectively of thediffusing and reflect-ing bowls diverge from each other downwardly,permitting a free assage of downwardly directed rays there etween.

Light distribution curves made using this light distributingconstruction show an in- `creased light distribution within the zoneover that given using the diffusing bowl alone, Vand show the lightdistribution above the 90 zone greatly reduced as compared with that ofthe diffusing bowl alone, but much greater than that obtained using Athemetal reflecting bowl alone. The combination of the two bowls gives aydifferent and improved result not obtained by the use of either bowlalone. All of the light which reaches the eye from above the angle ofcut-off either passes through the diffusing glass, or is reflected morethan once due to the shape of the glass and to its diffusingcharacteristic.

If desired, and as shown in Fig. 1, the diffusing bowl l() may have anupwardly extending conical portion 16 extending through the centrallopening in the reflector bowl 11 and a substantial distance thereaboveso as to allow some diffused light to "if escape.

The diffusing bowl 10 comprises adownwardly and outwardly extendingupper portion 17 and a downwardly and inwardly extending portion 18, andthe opaque reflector "V5 bowl or shade 11 comprises a downwardly andoutwardly extending upper portion 19 overlying the donf'nwardly andoutwardly extending portion 17 of the diffusing bowl. and a downwardlyand outwardly extending lower portion 20 surrounding the downn wardlyand inwardly extending lower por-Y tion 18 of the diffusing bowl.

Thile I have shown but one form of my invent-ion, it is to be understoodthat I do not desire to limit myself to this particular constructionsince many changes and modifieations may be made therein withoutdeparture from the scope of the following claim.

I claim: Y

A lighting fixture comprising a diffusing bowl of translucent materialhaving a downwardly and outwardly extending upper portion and adownwardly and inwardly extending lower portion, and an opaque reflectorshade having a downwardly and outwardly extending upper portionoverlyingr the downwardly and outwardly extending upper portion of thediffusing bowl and extending outwardly there-beyond, and having adownwardly and outwardly extending lower portion surrounding thedownwardly and inwardly extending lower portion ol' the diffusing bowl,the lower downwardly and inwardly extending portion of the dir- Yfusingbowl being` open in the bottom and extending below the lower edge of there- Hector shade, both the upper and lower portion of said reflectorshade being formed as Surfaces of revolution about a vertical axis.

scribed my naine.

HENRY DOLIER, JR.

